Hypersensitivity to lidocaine or any component of the formulation; hypersensitivity to another local anesthetic of the amide type; Adam-Stokes syndrome; severe degrees of SA, AV, or intraventricular heart block (except in patients with a functioning artificial pacemaker); premixed injection may contain corn-derived dextrose and its use is contraindicated in patients with allergy to corn-related products

Warnings / Precautions Drug

Concerns related to adverse effects:• Intra-articular infusion related chondrolysis: Continuous intra-articular infusion of local anesthetics after arthroscopic or other surgical procedures is not an approved use; chondrolysis (primarily in the shoulder joint) has occurred following infusion, with some cases requiring arthroplasty or shoulder replacement.Disease-related concerns:• Hepatic dysfunction: Use extreme caution in patients with severe hepatic dysfunction; may have increased risk of lidocaine toxicity.• Pseudocholinesterase deficiency: Use caution in patients with pseudocholinesterase deficiency; may have increased risk of lidocaine toxicityDosage form specific issues:• Injectable anesthetic: Follow appropriate administration techniques so as not to administer any intravascularly. Solutions containing antimicrobial preservatives should not be used for epidural or spinal anesthesia. Some solutions contain a bisulfite; avoid in patients who are allergic to bisulfite. Resuscitative equipment, medicine and oxygen should be available in case of emergency. Use products containing epinephrine cautiously in patients with significant vascular disease, compromised blood flow, or during or following general anesthesia (increased risk of arrhythmias). Adjust the dose for the elderly, pediatric, acutely ill, and debilitated patients.• Intravenous: Constant ECG monitoring is necessary during I.V. administration. Use cautiously in hepatic impairment, any degree of heart block, Wolff-Parkinson-White syndrome, HF, marked hypoxia, severe respiratory depression, hypovolemia, history of malignant hyperthermia, or shock. Increased ventricular rate may be seen when administered to a patient with atrial fibrillation. Correct electrolyte disturbances, especially hypokalemia or hypomagnesemia, prior to use and throughout therapy. Correct any underlying causes of ventricular arrhythmias. Monitor closely for signs and symptoms of CNS toxicity. The elderly may be prone to increased CNS and cardiovascular side effects. Reduce dose in hepatic dysfunction and CHF.Other warnings/precautions:• CAST trial: In the Cardiac Arrhythmia Suppression Trial (CAST), recent (>6 days but <2 years ago) myocardial infarction patients with asymptomatic, non-life-threatening ventricular arrhythmias did not benefit and may have been harmed by attempts to suppress the arrhythmia with flecainide or encainide. An increased mortality or nonfatal cardiac arrest rate (7.7%) was seen in the active treatment group compared with patients in the placebo group (3%). The applicability of the CAST results to other populations is unknown. Antiarrhythmic agents should be reserved for patients with life-threatening ventricular arrhythmias.Metabolism/Transport Effects Substrate of CYP1A2 (minor), CYP2A6 (minor), CYP2B6 (minor), CYP2C9 (minor), CYP2D6 (major), CYP3A4 (major), P-glycoprotein; Inhibits CYP1A2 (strong), 2D6 (moderate), 3A4 (moderate.

B Pregnancy Implications Animal studies with lidocaine have not shown teratogenic effects. Lidocaine and the MEGX metabolite cross the placenta. Use is not contraindicated during labor and delivery. Topical lidocaine is used locally to provide analgesia prior to episiotomy and during repair of obstetric lacerations. Administration by the perineal route may result in greater absorption than administration by the epidural route. Adverse events have been reported in the infant following maternal administration, however, when used in appropriate doses, the risk to the fetus is low. Cumulative exposure from all routes of administration should be considered.

Lactation

Enters breast milk/use caution (AAP rates “compatible”; AAP 2001 update pending)Breast-Feeding Considerations Small amounts of lidocaine and the MEGX metabolite are found in breast milk. The actual amount may depend on route and duration of administration. When administered topically at recommended doses, the amount of lidocaine available to the nursing infant would not be expected to cause adverse events. Cumulative exposure from all routes of administration should be considered.

Mechanism of Action

Class Ib antiarrhythmic; suppresses automaticity of conduction tissue, by increasing electrical stimulation threshold of ventricle, His-Purkinje system, and spontaneous depolarization of the ventricles during diastole by a direct action on the tissues; blocks both the initiation and conduction of nerve impulses by decreasing the neuronal membrane's permeability to sodium ions, which results in inhibition of depolarization with resultant blockade of conduction